Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262611AbUJ0S3A (ORCPT ); Wed, 27 Oct 2004 14:29:00 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262616AbUJ0SXg (ORCPT ); Wed, 27 Oct 2004 14:23:36 -0400 Received: from [129.105.5.125] ([129.105.5.125]:5114 "EHLO delta.ece.northwestern.edu") by vger.kernel.org with ESMTP id S262613AbUJ0STY (ORCPT ); Wed, 27 Oct 2004 14:19:24 -0400 Message-ID: <417FE703.3070608@ece.northwestern.edu> Date: Wed, 27 Oct 2004 13:20:51 -0500 From: Lei Yang User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4.2) Gecko/20040921 X-Accept-Language: en-us, en MIME-Version: 1.0 To: linux-kernel@vger.kernel.org Subject: loopback on block device X-Enigmail-Version: 0.76.8.0 X-Enigmail-Supports: pgp-inline, pgp-mime Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 808 Lines: 22 Hello, Here is a question for loopback device. As far as I understand, the loopback device is used to mount files as if they were block devices. Then Why I could do "losetup -e XOR /dev/loop0 /dev/ram0" ? Notice that ram0 is not mounted anywhere and does not have a filesystem on it. I've tried that command and there seems to be no error. I got confused and looked into loop.c, it seems to me that a loopback device should be associated with a "backing file", why would it work on a block device anyway? I'd appreciate your comments greatly! TIA, Lei - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/